A review of the literature suggests that several of the principal lesions of Alzheimer's lesion (AD) are present in a variety of conditions and represent a non-specific sustained molecular response to selected types of brain damage. We present evidence for amyloid toxicity in rat brain, plaque-associated and elevated basic FGF in the Alzheimer's brain and elevated basic FGF synthesis, and Alz-50, ubiquitin and beta protein immunoreactivity in response to injury in a rat model system. We propose to (1) quantify changes in basic FGF, Alz-50, ubiquitin, amyloid precursor protein (APP) and beta protein immunoreactivity induced in response to injury, (2) investigate the effect of immunoneutralization on microglial infiltration, reactive gliosis, AD antigens, and the synthesis of basic FGF, one of its receptor (Flg), and APP, (3) examine the effects of injury on the Alzheimer-related antigens, Alz-50, ubiquitin, beta protein, APP, and FGF by Western blot analysis, and (4) to determine the effects of injection of purified Alzheimer's brain plaque cores, (or control human brain extracts) and heparin beads (or beads alone) on infiltration of microglia, reactive gliosis, dendritic sprouting, AD antigens, dystrophic neurites, and sequestration of basic FGF and APP. Additional controls with synthetic amyloid and amyloid-related proteins will be used.